Solomon
Proverbs 15:28ESV·traditional attribution

The heart of the righteous ponders how to answer, but the mouth of the wicked pours out evil things.

Matthew Henry Presbyterian @wholebiblehenry

Here is, 1. A good man proved to be a wise man by this, that he governs his tongue well; he that does so the same is a perfect man, Jam 3:2. It is part of the character of a righteous man that being convinced of the account he must give of his words, and of the good and bad influence of them upon others...

John Gill Reformed Baptist @doctorgill

The heart of the righteous studieth to answer,.... He thinks before he speaks, meditates what he shall say, what answer to give to men; whether in things civil, natural, or religious; and what to return to the Lord when he is reproved by him; or what to say in prayer to him, or by way of thankfulness for mercies received from him; see Pro 3:6...

Jamieson-Fausset-Brown Reformed @jfbcommentary

(Compare Pro 15:14; Pro 10:11). Caution is the fruit of wisdom; rashness of folly.